net/mac80211/mesh.h - kernel/msm-4.19 - Gitiles

 /*
  * Copyright (c) 2008 open80211s Ltd.
  * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
  *             Javier Cardona <javier@cozybit.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #ifndef IEEE80211S_H
 #define IEEE80211S_H

 #include <linux/types.h>
 #include <linux/jhash.h>
 #include <asm/unaligned.h>
 #include "ieee80211_i.h"


 /* Data structures */

 /**
  * enum mesh_path_flags - mac80211 mesh path flags
  *
  *
  *
  * @MESH_PATH_ACTIVE: the mesh path is can be used for forwarding
  * @MESH_PATH_RESOLVED: the discovery process is running for this mesh path
  * @MESH_PATH_DSN_VALID: the mesh path contains a valid destination sequence
  * 	number
  * @MESH_PATH_FIXED: the mesh path has been manually set and should not be
  * 	modified
  * @MESH_PATH_RESOLVED: the mesh path can has been resolved
  *
  * MESH_PATH_RESOLVED and MESH_PATH_DELETE are used by the mesh path timer to
  * decide when to stop or cancel the mesh path discovery.
  */
 enum mesh_path_flags {
 	MESH_PATH_ACTIVE =	BIT(0),
 	MESH_PATH_RESOLVING =	BIT(1),
 	MESH_PATH_DSN_VALID =	BIT(2),
 	MESH_PATH_FIXED	=	BIT(3),
 	MESH_PATH_RESOLVED =	BIT(4),
 };

 /**
  * struct mesh_path - mac80211 mesh path structure
  *
  * @dst: mesh path destination mac address
  * @sdata: mesh subif
  * @next_hop: mesh neighbor to which frames for this destination will be
  * 	forwarded
  * @timer: mesh path discovery timer
  * @frame_queue: pending queue for frames sent to this destination while the
  * 	path is unresolved
  * @dsn: destination sequence number of the destination
  * @metric: current metric to this destination
  * @hop_count: hops to destination
  * @exp_time: in jiffies, when the path will expire or when it expired
  * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery
  * 	retry
  * @discovery_retries: number of discovery retries
  * @flags: mesh path flags, as specified on &enum mesh_path_flags
  * @state_lock: mesh pat state lock
  *
  *
  * The combination of dst and sdata is unique in the mesh path table. Since the
  * next_hop STA is only protected by RCU as well, deleting the STA must also
  * remove/substitute the mesh_path structure and wait until that is no longer
  * reachable before destroying the STA completely.
  */
 struct mesh_path {
 	u8 dst[ETH_ALEN];
 	struct ieee80211_sub_if_data *sdata;
 	struct sta_info *next_hop;
 	struct timer_list timer;
 	struct sk_buff_head frame_queue;
 	struct rcu_head rcu;
 	u32 dsn;
 	u32 metric;
 	u8 hop_count;
 	unsigned long exp_time;
 	u32 discovery_timeout;
 	u8 discovery_retries;
 	enum mesh_path_flags flags;
 	spinlock_t state_lock;
 };

 /**
  * struct mesh_table
  *
  * @hash_buckets: array of hash buckets of the table
  * @hashwlock: array of locks to protect write operations, one per bucket
  * @hash_mask: 2^size_order - 1, used to compute hash idx
  * @hash_rnd: random value used for hash computations
  * @entries: number of entries in the table
  * @free_node: function to free nodes of the table
  * @copy_node: fuction to copy nodes of the table
  * @size_order: determines size of the table, there will be 2^size_order hash
  *	buckets
  * @mean_chain_len: maximum average length for the hash buckets' list, if it is
  *	reached, the table will grow
  */
 struct mesh_table {
 	/* Number of buckets will be 2^N */
 	struct hlist_head *hash_buckets;
 	spinlock_t *hashwlock;		/* One per bucket, for add/del */
 	unsigned int hash_mask;		/* (2^size_order) - 1 */
 	__u32 hash_rnd;			/* Used for hash generation */
 	atomic_t entries;		/* Up to MAX_MESH_NEIGHBOURS */
 	void (*free_node) (struct hlist_node *p, bool free_leafs);
 	int (*copy_node) (struct hlist_node *p, struct mesh_table *newtbl);
 	int size_order;
 	int mean_chain_len;
 };

 /* Recent multicast cache */
 /* RMC_BUCKETS must be a power of 2, maximum 256 */
 #define RMC_BUCKETS		256
 #define RMC_QUEUE_MAX_LEN	4
 #define RMC_TIMEOUT		(3 * HZ)

 /**
  * struct rmc_entry - entry in the Recent Multicast Cache
  *
  * @seqnum: mesh sequence number of the frame
  * @exp_time: expiration time of the entry, in jiffies
  * @sa: source address of the frame
  *
  * The Recent Multicast Cache keeps track of the latest multicast frames that
  * have been received by a mesh interface and discards received multicast frames
  * that are found in the cache.
  */
 struct rmc_entry {
 	struct list_head list;
 	u32 seqnum;
 	unsigned long exp_time;
 	u8 sa[ETH_ALEN];
 };

 struct mesh_rmc {
 	struct rmc_entry bucket[RMC_BUCKETS];
 	u32 idx_mask;
 };


 /* Mesh IEs constants */
 #define MESH_CFG_LEN		19

 /*
  * MESH_CFG_COMP_LEN Includes:
  * 	- Active path selection protocol ID.
  * 	- Active path selection metric ID.
  * 	- Congestion control mode identifier.
  * 	- Channel precedence.
  * Does not include mesh capabilities, which may vary across nodes in the same
  * mesh
  */
 #define MESH_CFG_CMP_LEN 	17

 /* Default values, timeouts in ms */
 #define MESH_TTL 		5
 #define MESH_MAX_RETR	 	3
 #define MESH_RET_T 		100
 #define MESH_CONF_T 		100
 #define MESH_HOLD_T 		100

 #define MESH_PATH_TIMEOUT	5000
 /* Minimum interval between two consecutive PREQs originated by the same
  * interface
  */
 #define MESH_PREQ_MIN_INT	10
 #define MESH_DIAM_TRAVERSAL_TIME 50
 /* Paths will be refreshed if they are closer than PATH_REFRESH_TIME to their
  * expiration
  */
 #define MESH_PATH_REFRESH_TIME			1000
 #define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME)

 #define MESH_MAX_PREQ_RETRIES 4
 #define MESH_PATH_EXPIRE (600 * HZ)

 /* Default maximum number of established plinks per interface */
 #define MESH_MAX_ESTAB_PLINKS	32

 /* Default maximum number of plinks per interface */
 #define MESH_MAX_PLINKS		256

 /* Maximum number of paths per interface */
 #define MESH_MAX_MPATHS		1024

 /* Pending ANA approval */
 #define PLINK_CATEGORY		30
 #define MESH_PATH_SEL_CATEGORY	32

 /* Mesh Header Flags */
 #define IEEE80211S_FLAGS_AE	0x3

 /* Public interfaces */
 /* Various */
 u8 mesh_id_hash(u8 *mesh_id, int mesh_id_len);
 int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr);
 int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
 		struct ieee80211_sub_if_data *sdata);
 int mesh_rmc_check(u8 *addr, struct ieee80211s_hdr *mesh_hdr,
 		struct ieee80211_sub_if_data *sdata);
 bool mesh_matches_local(struct ieee802_11_elems *ie,
 		struct ieee80211_sub_if_data *sdata);
 void mesh_ids_set_default(struct ieee80211_if_sta *sta);
 void mesh_mgmt_ies_add(struct sk_buff *skb,
 		struct ieee80211_sub_if_data *sdata);
 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata);
 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata);
 void ieee80211s_init(void);
 void ieee80211s_stop(void);
 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);

 /* Mesh paths */
 int mesh_nexthop_lookup(struct sk_buff *skb,
 		struct ieee80211_sub_if_data *sdata);
 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata);
 struct mesh_path *mesh_path_lookup(u8 *dst,
 		struct ieee80211_sub_if_data *sdata);
 struct mesh_path *mesh_path_lookup_by_idx(int idx,
 		struct ieee80211_sub_if_data *sdata);
 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop);
 void mesh_path_expire(struct ieee80211_sub_if_data *sdata);
 void mesh_path_flush(struct ieee80211_sub_if_data *sdata);
 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
 		struct ieee80211_mgmt *mgmt, size_t len);
 int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata);
 /* Mesh plinks */
 void mesh_neighbour_update(u8 *hw_addr, u64 rates,
 		struct ieee80211_sub_if_data *sdata, bool add);
 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
 void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
 void mesh_plink_broken(struct sta_info *sta);
 void mesh_plink_deactivate(struct sta_info *sta);
 int mesh_plink_open(struct sta_info *sta);
 int mesh_plink_close(struct sta_info *sta);
 void mesh_plink_block(struct sta_info *sta);
 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
 			 struct ieee80211_mgmt *mgmt, size_t len,
 			 struct ieee80211_rx_status *rx_status);

 /* Private interfaces */
 /* Mesh tables */
 struct mesh_table *mesh_table_alloc(int size_order);
 void mesh_table_free(struct mesh_table *tbl, bool free_leafs);
 struct mesh_table *mesh_table_grow(struct mesh_table *tbl);
 u32 mesh_table_hash(u8 *addr, struct ieee80211_sub_if_data *sdata,
 		struct mesh_table *tbl);
 /* Mesh paths */
 int mesh_path_error_tx(u8 *dest, __le32 dest_dsn, u8 *ra,
 		struct ieee80211_sub_if_data *sdata);
 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta);
 void mesh_path_flush_pending(struct mesh_path *mpath);
 void mesh_path_tx_pending(struct mesh_path *mpath);
 int mesh_pathtbl_init(void);
 void mesh_pathtbl_unregister(void);
 int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata);
 void mesh_path_timer(unsigned long data);
 void mesh_path_flush_by_nexthop(struct sta_info *sta);
 void mesh_path_discard_frame(struct sk_buff *skb,
 		struct ieee80211_sub_if_data *sdata);

 #ifdef CONFIG_MAC80211_MESH
 extern int mesh_allocated;

 static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
 {
 	return sdata->u.sta.mshcfg.dot11MeshMaxPeerLinks -
 	       atomic_read(&sdata->u.sta.mshstats.estab_plinks);
 }

 static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
 {
 	return (min_t(long, mesh_plink_free_count(sdata),
 		   MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
 }

 static inline void mesh_path_activate(struct mesh_path *mpath)
 {
 	mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED;
 }

 #define for_each_mesh_entry(x, p, node, i) \
 	for (i = 0; i <= x->hash_mask; i++) \
 		hlist_for_each_entry_rcu(node, p, &x->hash_buckets[i], list)

 #else
 #define mesh_allocated	0
 #endif

 #endif /* IEEE80211S_H */
	/*
	* Copyright (c) 2008 open80211s Ltd.
	* Authors: Luis Carlos Cobo <luisca@cozybit.com>
	* Javier Cardona <javier@cozybit.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#ifndef IEEE80211S_H
	#define IEEE80211S_H

	#include <linux/types.h>
	#include <linux/jhash.h>
	#include <asm/unaligned.h>
	#include "ieee80211_i.h"


	/* Data structures */

	/**
	* enum mesh_path_flags - mac80211 mesh path flags
	*
	*
	*
	* @MESH_PATH_ACTIVE: the mesh path is can be used for forwarding
	* @MESH_PATH_RESOLVED: the discovery process is running for this mesh path
	* @MESH_PATH_DSN_VALID: the mesh path contains a valid destination sequence
	* number
	* @MESH_PATH_FIXED: the mesh path has been manually set and should not be
	* modified
	* @MESH_PATH_RESOLVED: the mesh path can has been resolved
	*
	* MESH_PATH_RESOLVED and MESH_PATH_DELETE are used by the mesh path timer to
	* decide when to stop or cancel the mesh path discovery.
	*/
	enum mesh_path_flags {
	MESH_PATH_ACTIVE = BIT(0),
	MESH_PATH_RESOLVING = BIT(1),
	MESH_PATH_DSN_VALID = BIT(2),
	MESH_PATH_FIXED = BIT(3),
	MESH_PATH_RESOLVED = BIT(4),
	};

	/**
	* struct mesh_path - mac80211 mesh path structure
	*
	* @dst: mesh path destination mac address
	* @sdata: mesh subif
	* @next_hop: mesh neighbor to which frames for this destination will be
	* forwarded
	* @timer: mesh path discovery timer
	* @frame_queue: pending queue for frames sent to this destination while the
	* path is unresolved
	* @dsn: destination sequence number of the destination
	* @metric: current metric to this destination
	* @hop_count: hops to destination
	* @exp_time: in jiffies, when the path will expire or when it expired
	* @discovery_timeout: timeout (lapse in jiffies) used for the last discovery
	* retry
	* @discovery_retries: number of discovery retries
	* @flags: mesh path flags, as specified on &enum mesh_path_flags
	* @state_lock: mesh pat state lock
	*
	*
	* The combination of dst and sdata is unique in the mesh path table. Since the
	* next_hop STA is only protected by RCU as well, deleting the STA must also
	* remove/substitute the mesh_path structure and wait until that is no longer
	* reachable before destroying the STA completely.
	*/
	struct mesh_path {
	u8 dst[ETH_ALEN];
	struct ieee80211_sub_if_data *sdata;
	struct sta_info *next_hop;
	struct timer_list timer;
	struct sk_buff_head frame_queue;
	struct rcu_head rcu;
	u32 dsn;
	u32 metric;
	u8 hop_count;
	unsigned long exp_time;
	u32 discovery_timeout;
	u8 discovery_retries;
	enum mesh_path_flags flags;
	spinlock_t state_lock;
	};

	/**
	* struct mesh_table
	*
	* @hash_buckets: array of hash buckets of the table
	* @hashwlock: array of locks to protect write operations, one per bucket
	* @hash_mask: 2^size_order - 1, used to compute hash idx
	* @hash_rnd: random value used for hash computations
	* @entries: number of entries in the table
	* @free_node: function to free nodes of the table
	* @copy_node: fuction to copy nodes of the table
	* @size_order: determines size of the table, there will be 2^size_order hash
	* buckets
	* @mean_chain_len: maximum average length for the hash buckets' list, if it is
	* reached, the table will grow
	*/
	struct mesh_table {
	/* Number of buckets will be 2^N */
	struct hlist_head *hash_buckets;
	spinlock_t hashwlock; / One per bucket, for add/del */
	unsigned int hash_mask; /* (2^size_order) - 1 */
	__u32 hash_rnd; /* Used for hash generation */
	atomic_t entries; /* Up to MAX_MESH_NEIGHBOURS */
	void (free_node) (struct hlist_node p, bool free_leafs);
	int (copy_node) (struct hlist_node p, struct mesh_table *newtbl);
	int size_order;
	int mean_chain_len;
	};

	/* Recent multicast cache */
	/* RMC_BUCKETS must be a power of 2, maximum 256 */
	#define RMC_BUCKETS 256
	#define RMC_QUEUE_MAX_LEN 4
	#define RMC_TIMEOUT (3 * HZ)

	/**
	* struct rmc_entry - entry in the Recent Multicast Cache
	*
	* @seqnum: mesh sequence number of the frame
	* @exp_time: expiration time of the entry, in jiffies
	* @sa: source address of the frame
	*
	* The Recent Multicast Cache keeps track of the latest multicast frames that
	* have been received by a mesh interface and discards received multicast frames
	* that are found in the cache.
	*/
	struct rmc_entry {
	struct list_head list;
	u32 seqnum;
	unsigned long exp_time;
	u8 sa[ETH_ALEN];
	};

	struct mesh_rmc {
	struct rmc_entry bucket[RMC_BUCKETS];
	u32 idx_mask;
	};


	/* Mesh IEs constants */
	#define MESH_CFG_LEN 19

	/*
	* MESH_CFG_COMP_LEN Includes:
	* - Active path selection protocol ID.
	* - Active path selection metric ID.
	* - Congestion control mode identifier.
	* - Channel precedence.
	* Does not include mesh capabilities, which may vary across nodes in the same
	* mesh
	*/
	#define MESH_CFG_CMP_LEN 17

	/* Default values, timeouts in ms */
	#define MESH_TTL 5
	#define MESH_MAX_RETR 3
	#define MESH_RET_T 100
	#define MESH_CONF_T 100
	#define MESH_HOLD_T 100

	#define MESH_PATH_TIMEOUT 5000
	/* Minimum interval between two consecutive PREQs originated by the same
	* interface
	*/
	#define MESH_PREQ_MIN_INT 10
	#define MESH_DIAM_TRAVERSAL_TIME 50
	/* Paths will be refreshed if they are closer than PATH_REFRESH_TIME to their
	* expiration
	*/
	#define MESH_PATH_REFRESH_TIME 1000
	#define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME)

	#define MESH_MAX_PREQ_RETRIES 4
	#define MESH_PATH_EXPIRE (600 * HZ)

	/* Default maximum number of established plinks per interface */
	#define MESH_MAX_ESTAB_PLINKS 32

	/* Default maximum number of plinks per interface */
	#define MESH_MAX_PLINKS 256

	/* Maximum number of paths per interface */
	#define MESH_MAX_MPATHS 1024

	/* Pending ANA approval */
	#define PLINK_CATEGORY 30
	#define MESH_PATH_SEL_CATEGORY 32

	/* Mesh Header Flags */
	#define IEEE80211S_FLAGS_AE 0x3

	/* Public interfaces */
	/* Various */
	u8 mesh_id_hash(u8 *mesh_id, int mesh_id_len);
	int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr);
	int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
	struct ieee80211_sub_if_data *sdata);
	int mesh_rmc_check(u8 addr, struct ieee80211s_hdr mesh_hdr,
	struct ieee80211_sub_if_data *sdata);
	bool mesh_matches_local(struct ieee802_11_elems *ie,
	struct ieee80211_sub_if_data *sdata);
	void mesh_ids_set_default(struct ieee80211_if_sta *sta);
	void mesh_mgmt_ies_add(struct sk_buff *skb,
	struct ieee80211_sub_if_data *sdata);
	void mesh_rmc_free(struct ieee80211_sub_if_data *sdata);
	int mesh_rmc_init(struct ieee80211_sub_if_data *sdata);
	void ieee80211s_init(void);
	void ieee80211s_stop(void);
	void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);

	/* Mesh paths */
	int mesh_nexthop_lookup(struct sk_buff *skb,
	struct ieee80211_sub_if_data *sdata);
	void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata);
	struct mesh_path mesh_path_lookup(u8 dst,
	struct ieee80211_sub_if_data *sdata);
	struct mesh_path *mesh_path_lookup_by_idx(int idx,
	struct ieee80211_sub_if_data *sdata);
	void mesh_path_fix_nexthop(struct mesh_path mpath, struct sta_info next_hop);
	void mesh_path_expire(struct ieee80211_sub_if_data *sdata);
	void mesh_path_flush(struct ieee80211_sub_if_data *sdata);
	void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
	struct ieee80211_mgmt *mgmt, size_t len);
	int mesh_path_add(u8 dst, struct ieee80211_sub_if_data sdata);
	/* Mesh plinks */
	void mesh_neighbour_update(u8 *hw_addr, u64 rates,
	struct ieee80211_sub_if_data *sdata, bool add);
	bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
	void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
	void mesh_plink_broken(struct sta_info *sta);
	void mesh_plink_deactivate(struct sta_info *sta);
	int mesh_plink_open(struct sta_info *sta);
	int mesh_plink_close(struct sta_info *sta);
	void mesh_plink_block(struct sta_info *sta);
	void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
	struct ieee80211_mgmt *mgmt, size_t len,
	struct ieee80211_rx_status *rx_status);

	/* Private interfaces */
	/* Mesh tables */
	struct mesh_table *mesh_table_alloc(int size_order);
	void mesh_table_free(struct mesh_table *tbl, bool free_leafs);
	struct mesh_table mesh_table_grow(struct mesh_table tbl);
	u32 mesh_table_hash(u8 addr, struct ieee80211_sub_if_data sdata,
	struct mesh_table *tbl);
	/* Mesh paths */
	int mesh_path_error_tx(u8 dest, __le32 dest_dsn, u8 ra,
	struct ieee80211_sub_if_data *sdata);
	void mesh_path_assign_nexthop(struct mesh_path mpath, struct sta_info sta);
	void mesh_path_flush_pending(struct mesh_path *mpath);
	void mesh_path_tx_pending(struct mesh_path *mpath);
	int mesh_pathtbl_init(void);
	void mesh_pathtbl_unregister(void);
	int mesh_path_del(u8 addr, struct ieee80211_sub_if_data sdata);
	void mesh_path_timer(unsigned long data);
	void mesh_path_flush_by_nexthop(struct sta_info *sta);
	void mesh_path_discard_frame(struct sk_buff *skb,
	struct ieee80211_sub_if_data *sdata);

	#ifdef CONFIG_MAC80211_MESH
	extern int mesh_allocated;

	static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
	{
	return sdata->u.sta.mshcfg.dot11MeshMaxPeerLinks -
	atomic_read(&sdata->u.sta.mshstats.estab_plinks);
	}

	static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
	{
	return (min_t(long, mesh_plink_free_count(sdata),
	MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
	}

	static inline void mesh_path_activate(struct mesh_path *mpath)
	{
	mpath->flags \|= MESH_PATH_ACTIVE \| MESH_PATH_RESOLVED;
	}

	#define for_each_mesh_entry(x, p, node, i) \
	for (i = 0; i <= x->hash_mask; i++) \
	hlist_for_each_entry_rcu(node, p, &x->hash_buckets[i], list)

	#else
	#define mesh_allocated 0
	#endif

	#endif /* IEEE80211S_H */